What arguments does Pope John Paul II use to justify his rejection of the priestly ordination of women & how does he support his arguments?

Pope John Paul II based his directions, presented in his letter "On Reserving Priestly Ordination to Men Alone," on the historic precedent that Jesus did not choose women to be included among the twelve apostles, his closest helpers while on Earth. In addition, the first persons chosen to help with spreading the word of the new church after Jesus's death were all men. For these reasons, Pope John Paul II concluded his letter by stating

I declare that the Church has no authority whatsoever to confer priestly ordination on women and that this judgment is to be definitively held by all the Church's faithful.

The letter does confirm the special significance of women in the church's ministry and mission, recognizing that the Blessed Virgin Mary's role as Mother of God as an indication of the important functions that women can fulfill in the church without being ordained.